Adding repeat mode to texture domain

src/gpu/effects/GrTextureDomain.h

 /*
  * Copyright 2012 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef GrTextureDomainEffect_DEFINED
 #define GrTextureDomainEffect_DEFINED
 
 #include "GrSingleTextureEffect.h"
 #include "gl/GrGLEffect.h"
 
 class GrGLShaderBuilder;
 struct SkRect;
 
 /**
  * Limits a texture's lookup coordinates to a domain. Samples outside the domain are either clamped
  * the edge of the domain or result in a vec4 of zeros (decal mode). The domain is clipped to
  * normalized texture coords ([0,1]x[0,1] square). Bilinear filtering can cause texels outside the
  * domain to affect the read value unless the caller considers this when calculating the domain.
  */
 class GrTextureDomain {
 public:
     enum Mode {
-        kIgnore_Mode,  // Ignore the texture domain rectangle.
-        kClamp_Mode,   // Clamp texture coords to the domain rectangle.
-        kDecal_Mode,   // Treat the area outside the domain rectangle as fully transparent.
+        // Ignore the texture domain rectangle.
+        kIgnore_Mode,
+        // Clamp texture coords to the domain rectangle.
+        kClamp_Mode,
+        // Treat the area outside the domain rectangle as fully transparent.
+        kDecal_Mode,
+        // Wrap texture coordinates.  NOTE: filtering may not work as expected because Bilerp will
+        // read texels outside of the domain.  We could perform additional texture reads and filter
+        // in the shader, but are not currently doing this for performance reasons
+        kRepeat_Mode,
 
-        kLastMode = kDecal_Mode
+        kLastMode = kRepeat_Mode
     };
     static const int kModeCount = kLastMode + 1;
 
     static const GrTextureDomain& IgnoredDomain() {
         static const SkRect gDummyRect = {0, 0, 0, 0};
         static const GrTextureDomain gDomain(gDummyRect, kIgnore_Mode);
         return gDomain;
     }
 
     /**
@@ skipping 125 matching lines @@
                           GrCoordSet);
 
     virtual bool onIsEqual(const GrEffect&) const SK_OVERRIDE;
 
     GR_DECLARE_EFFECT_TEST;
 
     typedef GrSingleTextureEffect INHERITED;
 };
 
 #endif